Ether prices slumped 8.1% on Friday while bitcoin lost 2%, while the market capitalization of digital assets tracked by CoinMarketCap.com shrank to $196 billion

The cryptocurrency bear market plumbed a fresh 10-month low, led by a tumble in Bitcoin’s biggest rival. Ether slumped 8.1 percent from its level at 5 p.m. New York time on Friday, according to Bloomberg composite pricing. Bitcoin lost 2 percent, while the market capitalization of digital assets tracked by CoinMarketCap.com shrank to $196 billion, down about $640 billion from its January peak.

The Bloomberg Galaxy Crypto Index of major virtual currencies has declined for five of the past six weeks amid concern that a broader adoption of digital assets will take longer than some had anticipated. That worry was underscored over the weekend after the U.S. Securities and Exchange Commission temporarily suspended trading in two securities linked to cryptocurrencies and Ethereum co-founder Vitalik Buterin told Bloomberg that the days of explosive growth in the blockchain industry have likely come and gone.

Cryptocurrencies remained under pressure on Monday despite reports that Citigroup Inc. has developed a new mechanism for investing in digital assets. The bank plans to act as an agent issuing so-called digital asset receipts, or DARs, to enable trading by proxy without direct ownership of the underlying coins, a person with knowledge of the plans said.

The Bloomberg Galaxy Crypto Index fell 3.5 percent as of 10:02 a.m. in Hong Kong, heading for the lowest close since mid-November.